public class Test4 {
    public static void main(String[] args) {

        double num = 0;
        for (int i = 1;i <= 10; i++) {
            long a = 1;
            for (int j=1; j<= i; j++) {
                a = a * j;
            }
            num += (double) 1 / a;
        }
        System.out.println(" = " + num);
    }
}
